Furnace charging apparatus

ABSTRACT

A raw material distribution chute is rotated when inner and outer cylinders are rotated in unison, and is tilted when the inner or outer cylinder is vertically moved with respect to the outer or inner cylinder. The rotation and tilting of the distribution chute may be made simultaneously or individually so that the pattern of raw material distribution may be varied over a wide range.

United States Patent 1 1 Furuya et al.

[ 1 FURNACE CHARGING APPARATUS [75] Inventors: Shoji Furuya, Tokyo; Masaoki Takahashi; Masatoshi Matsushima, both of Yokohama, all of Japan Ishikawajima-Harima Jukogyo Kabushiki Kaisha, Tokyo, Japan [22] Filed: Jan. 30, 1974 [21] Appl. No.: 437,809

[7 3] Assignee:

[30] Foreign Application Priority Data Jan. 31, 1973 Japan 48-12649 [52] US. Cl. 214/35 R; 193/3; 214/17 CB; 266/27 [51] Int. Cl. F27b 1/20 [58] Field of Search 214/17 CB, 18 V, 35 R, 214/36, 37; 193/3; 266/27; 302/60 [451 Aug. 12, 1975 [56] References Cited UNITED STATES PATENTS 3,693,812 9/1972 Mahr 214/35 R Primary ExaminerRobert G. Sheridan Attorney, Agent, or FirmScrivener Parker Scrivener & Clarke [57] ABSTRACT A raw material distribution chute is rotated when inner and outer cylinders are rotated in unison, and is tilted when the inner or outer cylinder is vertically moved with respect to the outer or inner cylinder. The rotation and tilting of the distribution chute may be made simultaneously or individually so that the pattern of raw material distribution may be varied over a wide range.

3 Claims, 4 Drawing Figures PATENTEU 2W5 3,899,088

SHEET 1 R/0F? HRT A 2 MM Milli \W/ PATENTEB AUG '1 2 I975 SHEET FURNACE CHARGING APPARATUS The present invention relates to a mechanism for driving a device for charging raw materials into a blast furnace.

The following conditions must be satisfied in order to charge the raw materials through a chute into a blast furnace from its top:

I. The charging position in the furnace must be freely selected in order to accomplish the highly efficient furnace operation depending upon the conditions of the furnace and the qualities of raw materials.

ll. The mechanism must withstand the high temperature furnace gases containing a large amount of dusts (the temperature being 200 300C under the normal conditions and 700 1,000C in case of slip and blast.

lll. Since the chute is subjected to abrasive wear, it must have a simple construction so as to be replaced and repaired in a simple manner. The chute driving mechanism, which is one of the most important factors affecting the furnace operation, also must have a simple construction so as to permit the simple inspection and maintenance.

IV. The complete gas-tightness must be provided for a blast furnace of the recent type using a high blast pressure because the leakage of poisonous gases is hazardous to the health of the operators engaging in the inspection and maintenance of the raw material charging mechanism and brings about the air pollution problem. Furthermore, the furnace gas leakage causes gas cuts at the leaking portions.

One of the objects of the present invention is therefore to provide a mechanism for driving a device for charging raw materials into a blast furnace which mechanism is prevented from being exposed to high temperature furnace gases and dusts. Another object of the present invention is to prevent the malfunction and abrasive wear of the driving mechanism due to the intrusion of the dusts.

A further object of the present invention is to ensure the satisfactory operation of the driving mechanism even without using nitrogen gas.

A further object of the present invention is to provide a driving mechanism of the type described whose inspection and maintenance may be accomplished during the furnace operation so that the sudden interruption of blast may be prevented, thereby preventing the decrease in iron production.

The above and other objects, features and advantages of the present invention will become more apparent from the following description of preferred embodiments thereof taken in conjunction with the accompanying drawing in which:

FIG. 1 is a schematic view of a conventional device incorporating a conventional driving mechanism for charging raw materials into a blast furnace from its top;

FIG. 2 is a fragmentary sectional view of the conventional driving mechanism;

FIG. 3 is a sectional view of a first embodiment of a driving mechanism in accordance with the present invention; and

FIG. 4 is a sectional view of a second embodiment of the present invention.

Prior to the description of the preferred embodiments of the present invention, the conventional device for charging raw materials into a blast furnace will be briefly described with reference to FIGS. 1 and 2 in order to point out its distinct defects, which the present invention contemplates to overcome. A seal hopper b with seal valves a and a is joined to a charging hopper c in such a way that raw materials may be charged into 5 the seal hopper b when the seal valve a is opened and the raw materials charged into the hopper b are charged into the furnace through a fixed charging opening d when the seal valve a at the lower end of the hopper b is opened. A distribution chute e is disposed within the furnace in such a manner that the raw materials may be distributed into the furnace.

The mechanism for driving the chute e is illustrated in FIG. 2. Within the space between the outer side wall of the fixed charging opening d and a seal cover f joined to the top of the furnace are disposed an inner cylinder g having a gear h fixed at the top thereof and an outer cylinder 1' having a gear j fixed at the top thereof. A push rod 1 housed within a guide cylinder m, which in turn is disposed between the inner and outer cylinders g and i, has a roller n fitted into a groove k of the outer cylinder 1'. The chute e which is pivoted with pins 0 to the lower end of the fixed charging opening d is connected to the lower end of the push rod 1. Gears p and q in mesh with the gears h and j, respectively, are drivingly coupled to motors r and s, respectively, so that the inner and outer cylinders g and i may be rotated simultaneously or individually with respect to each other, thereby rotating and swinging or tilting the distribution chute e.

While the motors r and s are disposed outside of the furnace, the gears p, q, /1, and j are disposed within the seal cover f and hence the furnace so that the parts disposed within the space between the seal cover f and the fixed charging opening d are always exposed to the high temperature furnace gases. Furthermore, dust intrudes into this space. Therefore, the malfunction and abrasive wear of the parts occur. To overcome these problems, nitrogen is forced into the space through a port I so as to cool the parts within the space, thereby preventing the malfunctions and abrasive wear of the parts. However, there arises a problem when a suitable nitrogen source is not available or the supply of nitrogen gas is interrupted. Furthermore, the above countermeasure does not provide the complete cooling and gas-tightness. Therefore the important parts such as gears which are essential in blast furnace operation cannot be completely protected, so that the breakdown of these parts result in the sudden interruption of blast, thus causing the reduction in iron production. Furthermore, since these parts are within the blast furnace their inspection and maintenance cannot be accomplished while the furnace is in operation so that the safety in operation cannot be sufficiently ensured. First Embodiment, FlG. 3.

Referring to FIG. 3, an inner cylinder 1 carried by a ring gear 2 coaxially thereof, and lined with antiabrasive wear material 3, and an outer cylinder 4 with a flange 5 are disposed in a top 16 of a blast furnace coaxially thereof. The ring gear 2 is supported by a rotary support device 6 which in turn is supported on a stationary member such as a deck on the furnace top. The ring gear 2 is drivingly coupled through an idle gear 8 to a motor 7 so that the inner cylinder 1 may be rotated. The flange 5 of the outer cylinder 4 is supported by a rotary support device 10 which in turn is supported by a plurality of power cylinders 9, so that the outer cylinder 4 may be vertically moved with respect to the inner cylinder 1 by the cylinders 9. Vertical guides l 1 extended from the outer side wall of the inner cylinder 1 are fitted into corresponding guide grooves 12 formed in the inner wall of the outer cylinder 4 so that the outer cylinder 4 may be permitted to slide vertically with respect to the inner cylinder 1 but is prevented by freely rotating with respect to the inner cylinder 1. A distribution chute 13 which is pivoted to the lower end of the inner cylinder 1 with pivot pins 14 has its inner walls lined with abrasive wear resulting material and its outer walls lined with refractory material. The distribution chute 13 is also connected through links 15 to the lower end of the outer cylinder 4. Therefore, the distribution chute 13 is rotated about the axis of the furnace when the inner and outer cylinders 1 and 4 are rotated in unison by the motor 7, and when the outer cylinder 4 is vertically moved with respect to the inner cylinder 1, the distribution chute 13 may swing or tilt about the pivot pins 14 so that the angle of the outlet of the chute 13 with respect to the axis of the furnace may be suitably varied. Thus, the raw materials may be directly distributed in the blast furnace by the distribution chute 13.

Sealing means 18 which is adapted to be cooled by cooling means 17 is interposed between the outer cylinder 4 and the top 16 of the furnace, and seal means 19 is interposed between the inner cylinder 1 and the rotary support device 10 and between the outer cylinder 4 and the rotary support device 10. Seal means is also interposed between the upper end portion of the inner cylinder 1 and a raw material charging chute 21. Therefore, the complete gas-tightness is provided. It should be noted that the inner and outer cylinders 1 and 4 are driven by the motor 7 which is located outside of the furnace.

Next the mode of operation will be described. When it is desired to distribute the raw materials about the axis of the furnace, the power cylinders 9 are actuated to drive the outer cylinder so as to control the angle of inclination of the distribution chute 13. Thereafter, the motor 7 is driven to rotate the inner and outer cylinders 1 and 4 in unison so that the distribution chute 13 is rotated about the axis of the furnace. Therefore, the raw materials charged into the inner cylinder 1 from the chute 21 may be distributed along a circle within the furnace. The diameter of this circle may be varied by controlling the angle of the distribution chute 13 and hence the position of the outer cylinder 4 so that the raw materials may be distributed from the axis of the furnace to the furnace wall in any desired manner.

Furthermore, according to the present invention, the position of the outer cylinder 4 with respect to the inner cylinder 1 and hence the angle of the distribution chute 13 with respect to the axis of the furnace may be varied independently of the rotation of the inner and outer cylinders l and 4. Therefore, when the angle of the distribution chute 13 is varied while the rotation of the inner and outer cylinders 1 and 4 is stopped, the raw materials may be distributed in the radial direction of the furnace or the spot charging of the raw materials may become possible. When the distribution chute 13 is retracted to the position indicated by the two-dot chain lines in FIG. 3, the raw materials may be charged dirctly from the inner cylinder 1 into the furnace. Furthermore, when the motor 7 and the power cylinder 9 are suitably controlled, the pattern of raw material distribution in the furnace may be controlled continuously or from one spot to another.

When the replacement or repair of the distribution chute 13 is required, it may be directly removed out of the opening through the top 16, but it is preferable to remove the seal means 18 and to release the support devices 6 and 10 so that the outer and inner cylinders 1 and 4 and the distribution chute 13 may be lifted in unison from the top 16. Thus, the replacement or repair of the distribution chute 13 may be accomplished outside of the furnace.

Second Embodiment, FIG. 4

Next referring to FIG. 4, the second embodiment of the present invention will be described. Unlike the first embodiment in which the inner cylinder 1 rotates the outer cylinder 4 and the outer cylinder 4 is vertically moved with respect to the inner cylinder 1, the arrangement of the second embodiment is such that the flange 5 of the inner cylinder 1 is supported by the rotary support device 10 which in turn is supported through the power cylinders 9 on a deck 22 on the top of the furnace, and the outer cylinder 4 is supported by the ring gear 2 which in turn is supported by the rotary support device 6 disposed on the deck 22. As in the case of the first embodiment, the motor 7 is drivingly coupled through a pinion 8 to the ring gear 2 so that the outer and inner cylinders 4 and 1 may be rotated in unison. The vertical guides 11 of the inner cylinder 1 are fitted into the corresponding guide grooves 12 of the outer cylinder 4 so that the inner cylinder 1 may be rotated in unison with the outer cylinder 4 and may be permitted to vertically move with respect to the outer cylinder 4. The distribution chute 13 whose inner and outer walls are lined with abrasive wear resisting material 23 and refractory material 24, respectively, is pivoted to the lower end of the outer cylinder 4 with the pivot pins 14 and is operatively coupled through the links 15 to the inner cylinder 1. Therefore, the distribution chute 13 may be rotated in unison with the inner and outer cylinders 1 and 4 and may swing about the pivot pins 14 when the inner cylinder 1 is vertically moved with respect to the outer cylinder 4. Seal means are interposed between the outer cylinder 4 and the furnace top 16, between the inner and outer cylinders 1 and 4, and between the inner cylinder 1 and the charging chute 21 so that the complete gas-tightness may be provided. As in the case of the first embodiment, the inner and outer cylinders 1 and 4 and the distribution chute 13 may be driven from the motor 7 and the power cylinders 9 disposed outside of the furnace.

The second embodiment may also distribute the raw materials in the furnace in a manner substantially similar to that described with reference to the first embodiment.

The foregoing description is merely an illustration of the preferred embodiments of the present invention and is not intended to limit the invention to these illustrative embodiments. For instance, instead of using the links 15 for interconnecting between the distribution chute 13 and the outer or inner cylinder 4 or 1, a rack and pinion, a cam device or any other suitable means may be used. It is to be understood that in addition to the above, various modifications can be effected within the true spirit of the present invention. The driving mechanisms of the present invention may be also incorporated into a blast furnace with a bell.

The features and advantages of the driving mechanisms of the present invention may be summarized as follows:

i. The motor and power cylinders for driving the distribution chute are all installed outside of the furnace so that they may be completely protected from the high temperature furnace gases and may be inspected and repaired at any time even in case of the furnace operation.

ii. The use of nitrogen gas may be eliminated, and the prior art seal means may be used. Since the complete gas-tightness is provided, the service life of various parts on the top of the furnace may be increased, and the safety in inspection and maintenance may be ensured.

iii. Since the rotation of the inner and outer cylinders and the vertical movement of the outer or inner cylinder may be made independently of each other, the rotation and swing or tilting of the distribution chute may be combined in various manners so that the pattern of raw material distribution in the furnace may be varied freely.

iv. Seal means interposed between the furnace and the device for charging the raw materials is rotatable and slidable so that the expansion of the furnace in the vertical direction may be absorbed without using the expansion joints.

What is claimed is:

l. Mechanism for charging a furnace with raw materials through a top opening comprising a distribution chute positioned in the upper portion of the furnace adjacent the opening, means for mounting said chute for rotation about the vertical axis of the furnace and for independent angular adjustment with respect to said axis, a pair of concentrically arranged cylinders positioned exteriorally of said furnace and aligned with said vertical axis, said cylinders being connected for rotation together and slideable movement with respect to each other, first power means for rotating said cylinders, second power means for slideably moving one cylinder with respect to the other, means connecting one of the cylinders with the chute to rotate the latter upon operation of said first power means, and means connecting the other cylinder with the chute for angular adjustment of the latter upon operation of said second power means.

2. Mechanism as set forth in claim 1 which includes interengaging vertically arranged rails and grooves formed on said cylinders to enable slideable movement of one with respect to the other.

3. Mechanism as set forth in claim 2 wherein one cylinder is provided with a ring gear operatively connected with the first power means. 

1. Mechanism for charging a furnace with raw materials through a top opening comprising a distribution chute positioned in the upper portion of the furnace adjacent the opening, means for mounting said chute for rotation about the vertical axis of the furnace and for independent angular adjustment with respect to said axis, a pair of concentrically arranged cylinders positioned exteriorally of said furnace and aligned with said vertical axis, said cylinders being connected for rotation together and slideable movement with respect to each other, first power means for rotating said cylinders, second power means for slideably moving one cylinder with respect to the other, means connecting one of the cylinders with the chute to rotate the latter upon operation of said first power means, and means connecting the other cylinder with the chute for angular adjustment of the latter upon operation of said second power means.
 2. Mechanism as set forth in claim 1 which includes interengaging vertically arranged rails and grooves formed on said cylinders to enable slideable movement of one with respect to the other.
 3. Mechanism as set forth in claim 2 wherein one cylinder is provided with a ring gear operatively connected with the first power means. 